The proposed amount of $6.2 billion settles a long-running class-action lawsuit with retailers over the fees they pay when accepting card payments

Mastercard Inc., Visa Inc. and other financial institutions have agreed to settle a long-running antitrust lawsuit with merchants over the fees they pay when they accept card payments for a proposed settlement amount of about $6.2 billion.

The proposed amount includes $900 million from all of the defendants, including a number of banks that issue debit and credit cards, including JPMorgan Chase & Co., Citigroup Inc., and Bank of America Corp. It also includes roughly $5.3 billion already paid by the defendants as part...